Off-campus UNL users: To download campus access dissertations,
please use the following link to log into our proxy server with your NU ID and password. When you are done browsing please remember to return to this page and log out.

Abstract

This study is part of a multi-phase investigation aimed at contributing evidence regarding the validity of a newly developed parent report measure designed to assess the prelexical vocal and early lexical development of infants and toddlers who are deaf and hard of hearing, ages 6 to 21 months. The measure, the Vocal Development Landmarks Interview (VDLI), is a 22-item interactive parent-report interview that uses audio samples of authentic infant vocalizations presented in a paired-comparison format to help make vocal landmarks clear and understandable to parents. The primary purpose of the study was to examine the extent to which parents and an examiner agree in their judgments of infant vocal behaviors surveyed on the VDLI. Vocal recordings of 40 children with normal hearing whose parents were interviewed using the VDLI were analyzed, coded, and scored by a trained examiner and compared to parents’ VDLI responses. Parent-examiner agreement was assessed using two different scoring approaches: 1) adjacency and 2) presence-absence. Factors contributing to variance in parent-examiner agreement and developmental patterns in the proportions of vocal behaviors observed in the young children were also explored. Results based on adjacency scoring indicated acceptable overall agreement, but highlighted a potential confound with the frequency-based items on the scale. Results based on presence-absence scoring revealed high overall agreement, indicating that parents and the examiner were often in agreement regarding vocal behaviors produced by children in this sample. Proportions of vocal behaviors observed in this sample aligned well with the expected developmental trajectory. These findings show promise for the use of the VDLI as a tool to evaluate developmental changes in infants’ vocalizations, while highlighting the need for potential modification of the scale going forward as it is applied with different populations of children who are deaf and hard of hearing.^